The history of the sea based transport from harbors and across the high seas includes passive methods and apparatuses intended to stop ships or at least impede the rapid proceeding of a ship under way.
Examples of methods for impeding passage of a ship underway include buoyant and semi-buoyant mines that have been used to blow holes in ships and sink them. In other examples, nets, chains and ropes have been employed at harbor entrances or restricted waterway to stop and ensnare propellers and rudders of sea going vessels. Still other examples include ensnaring cables around a ship propeller to impede the propeller from turning from operating at full speed and perhaps stalling the engines all together.
Some known technologies such as U.S. Pat. No. 8,245,617 (the '617 Patent) described methods of deploying immobilization devices that use sticky tendrils to ensnare land or water borne vehicles. The '617 Patent was based upon an entangling device including a drag chute that is dragged by a vessel and illustrates the entangling device being entangled on the propeller. The principle method of attachment described by the '617 Patent is based on “entanglement”.
In addition, the method described in 617 assumed the “immobilization” would come from the “entangling apparatus” which is intended to “foul or render a large prop”. The apparatus included a “drag chute” connected to a “strap” which implies the tension or drag from the “drag chute” is not the principal modality of slowing the vessel. A “strap” is generally known to be made of cloth or flexible material and not generally known to be strong nor as the principle method by which the vessel is slowed.
The methods listed above, tend to be destructive to the ships involved and also expensive both in the deployment of the apparatus and the damage to the ship and perhaps harm to a crew on a ship impacted by such devices.
The need therefore remains for apparatus and methods to enable large-scale and low-cost deployment of non-lethal ship-slowing technology to impede normal passage of a ship underway.